贵州省猪源沙门氏菌Ⅰ类整合子与耐药基因盒研究

Research on Integron Class Ⅰ and Drug Resistance Gene Cassette in Swine Salmonella in Guizhou

为了调查规模养殖场沙门氏菌中Ⅰ类整合子的流行情况,采用聚合酶链式反应检测了从贵州省规模养猪场分离的57株沙门氏菌中Ⅰ类整合子的携带率以及整合子中耐药基因盒的种类;采用微量肉汤稀释法测定了57株沙门氏菌对12种抗菌药物的敏感性;并应用χ2检验检测Ⅰ类整合子阳性菌株与阴性菌株耐药性的相关性。结果显示,57株沙门氏菌中Ⅰ类整合子检出率为40.4%(23/57);耐药基因盒检出率为31.6%(18/57);整合子中携带可分别介导对氨基糖苷类和磺胺类药物耐药的aad A2、aad A5、aad A22、aad A23b、dfr A1、dfr A12和dfr A17基因;57株沙门氏菌对12种抗菌药物的耐药率不同,Ⅰ类整合子与多重耐药之间有明显的相关性。

To investigate the prevalence state of classⅠ integron in Salmonella,the carrying rates of classⅠ integrons and the types of drug resistance gene cassettes of 57 Salmonella strains isolated from scale swine farms were determined by polymerase chain reaction（ PCR）. The susceptibility of the Salmonella strains to 12 antimicrobial was tested by the broth dilution method. The correlation of anti- microbial resistance between the positive and negative strains of classⅠ integron was analyzed by χ^2 test. The results showed that the carrying rate of classⅠ integrons and drug resistance gene cassettes was 40. 4%（ 23 /57） and 31. 6%（ 18 /57） respectively. The genes of aad A2,aad A5,aad A22,aad A23 b,dfr A1,dfr A12 and dfr A17 were checked out in classⅠ integrons,which mediated Salmonella resistance to aminoglycoside antibiotics and sulfa drug resistance respectively. Fifty seven strains of Salmonella had different drug resistance rates to 12 antimicrobial. The gene cassette carried in classⅠ integron presented obvious relativity to multi- drug- resistance（ MDR）.